Create.c

   1 /*
   2  * mdadm - manage Linux "md" devices aka RAID arrays.
   3  *
   4  * Copyright (C) 2001-2002 Neil Brown <neilb@cse.unsw.edu.au>
   5  *
   6  *
   7  *    This program is free software; you can redistribute it and/or modify
   8  *    it under the terms of the GNU General Public License as published by
   9  *    the Free Software Foundation; either version 2 of the License, or
  10  *    (at your option) any later version.
  11  *
  12  *    This program is distributed in the hope that it will be useful,
  13  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *    GNU General Public License for more details.
  16  *
  17  *    You should have received a copy of the GNU General Public License
  18  *    along with this program; if not, write to the Free Software
  19  *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20  *
  21  *    Author: Neil Brown
  22  *    Email: <neilb@cse.unsw.edu.au>
  23  *    Paper: Neil Brown
  24  *           School of Computer Science and Engineering
  25  *           The University of New South Wales
  26  *           Sydney, 2052
  27  *           Australia
  28  */
  29
  30 #include "mdadm.h"
  31 #include        "md_u.h"
  32 #include        "md_p.h"
  33
  34 int Create(char *mddev, int mdfd,
  35            int chunk, int level, int layout, int size, int raiddisks, int sparedisks,
  36            int subdevs, mddev_dev_t devlist,
  37            int runstop, int verbose, int force)
  38 {
  39         /*
  40          * Create a new raid array.
  41          *
  42          * First check that necessary details are available
  43          * (i.e. level, raid-disks)
  44          *
  45          * Then check each disk to see what might be on it
  46          * and report anything interesting.
  47          *
  48          * If anything looks odd, and runstop not set,
  49          * abort.
  50          *
  51          * SET_ARRAY_INFO and ADD_NEW_DISK, and
  52          * if runstop==run, or raiddisks diskswere used,
  53          * RUN_ARRAY
  54          */
  55         int minsize=0, maxsize=0;
  56         char *mindisc = NULL;
  57         char *maxdisc = NULL;
  58         int dnum;
  59         mddev_dev_t dv;
  60         int fail=0, warn=0;
  61         struct stat stb;
  62         int first_missing = MD_SB_DISKS*2;
  63         int missing_disks = 0;
  64         int insert_point = MD_SB_DISKS*2; /* where to insert a missing drive */
  65
  66         mdu_array_info_t array;
  67
  68
  69         if (md_get_version(mdfd) < 9000) {
  70                 fprintf(stderr, Name ": Create requires md driver verison 0.90.0 or later\n");
  71                 return 1;
  72         }
  73         if (level == -10) {
  74                 fprintf(stderr,
  75                         Name ": a RAID level is needed to create an array.\n");
  76                 return 1;
  77         }
  78         if (raiddisks < 1) {
  79                 fprintf(stderr,
  80                         Name ": a number of --raid-devices must be given to create an array\n");
  81                 return 1;
  82         }
  83         if (raiddisks < 2 && level >= 4) {
  84                 fprintf(stderr,
  85                         Name ": atleast 2 raid-devices needed for level 4 or 5\n");
  86                 return 1;
  87         }
  88         if (raiddisks+sparedisks > MD_SB_DISKS) {
  89                 fprintf(stderr,
  90                         Name ": too many devices requested: %d+%d > %d\n",
  91                         raiddisks, sparedisks, MD_SB_DISKS);
  92                 return 1;
  93         }
  94         if (subdevs > raiddisks+sparedisks) {
  95                 fprintf(stderr, Name ": You have listed more devices (%d) than are in the array(%d)!\n", subdevs, raiddisks+sparedisks);
  96                 return 1;
  97         }
  98         if (subdevs < raiddisks+sparedisks) {
  99                 fprintf(stderr, Name ": You haven't given enough devices (real or missing) to create this array\n");
 100                 return 1;
 101         }
 102
 103         /* now set some defaults */
 104         if (layout == -1)
 105                 switch(level) {
 106                 default: /* no layout */
 107                         layout = 0;
 108                         break;
 109                 case 5:
 110                         layout = map_name(r5layout, "default");
 111                         if (verbose)
 112                                 fprintf(stderr,
 113                                         Name ": layout defaults to %s\n", map_num(r5layout, layout));
 114                         break;
 115                 }
 116
 117         if (chunk == 0) {
 118                 chunk = 64;
 119                 if (verbose)
 120                         fprintf(stderr, Name ": chunk size defaults to 64K\n");
 121         }
 122
 123         /* now look at the subdevs */
 124         array.active_disks = 0;
 125         array.working_disks = 0;
 126         dnum = 0;
 127         for (dv=devlist; dv; dv=dv->next, dnum++) {
 128                 char *dname = dv->devname;
 129                 int dsize, freesize;
 130                 int fd;
 131                 if (strcasecmp(dname, "missing")==0) {
 132                         if (first_missing > dnum)
 133                                 first_missing = dnum;
 134                         missing_disks ++;
 135                         continue;
 136                 }
 137                 array.working_disks++;
 138                 if (dnum < raiddisks)
 139                         array.active_disks++;
 140                 fd = open(dname, O_RDONLY, 0);
 141                 if (fd <0 ) {
 142                         fprintf(stderr, Name ": Cannot open %s: %s\n",
 143                                 dname, strerror(errno));
 144                         fail=1;
 145                         continue;
 146                 }
 147                 if (ioctl(fd, BLKGETSIZE, &dsize)) {
 148                         fprintf(stderr, Name ": Cannot get size of %s: %s\n",
 149                                 dname, strerror(errno));
 150                         fail = 1;
 151                         close(fd);
 152                         continue;
 153                 }
 154                 if (dsize < MD_RESERVED_SECTORS*2) {
 155                         fprintf(stderr, Name ": %s is too small: %dK\n",
 156                                 dname, dsize/2);
 157                         fail = 1;
 158                         close(fd);
 159                         continue;
 160                 }
 161                 freesize = MD_NEW_SIZE_SECTORS(dsize);
 162                 freesize /= 2;
 163
 164                 if (size && freesize < size) {
 165                         fprintf(stderr, Name ": %s is smaller that given size."
 166                                 " %dK < %dK + superblock\n", dname, freesize, size);
 167                         fail = 1;
 168                         close(fd);
 169                         continue;
 170                 }
 171                 if (maxdisc == NULL || (maxdisc && freesize > maxsize)) {
 172                         maxdisc = dname;
 173                         maxsize = freesize;
 174                 }
 175                 if (mindisc ==NULL || (mindisc && freesize < minsize)) {
 176                         mindisc = dname;
 177                         minsize = freesize;
 178                 }
 179                 warn |= check_ext2(fd, dname);
 180                 warn |= check_reiser(fd, dname);
 181                 warn |= check_raid(fd, dname);
 182                 close(fd);
 183         }
 184         if (fail) {
 185                 fprintf(stderr, Name ": create aborted\n");
 186                 return 1;
 187         }
 188         if (size == 0) {
 189                 if (mindisc == NULL) {
 190                         fprintf(stderr, Name ": no size and no drives given - aborting create.\n");
 191                         return 1;
 192                 }
 193                 size = minsize;
 194                 if (verbose && level>0)
 195                         fprintf(stderr, Name ": size set to %dK\n", size);
 196         }
 197         if (level >= 1 && ((maxsize-size)*100 > maxsize)) {
 198                 fprintf(stderr, Name ": largest drive (%s) exceed size (%dK) by more than 1%%\n",
 199                         maxdisc, size);
 200                 warn = 1;
 201         }
 202
 203         if (warn) {
 204                 if (runstop!= 1) {
 205                         if (!ask("Continue creating array? ")) {
 206                                 fprintf(stderr, Name ": create aborted.\n");
 207                                 return 1;
 208                         }
 209                 } else {
 210                         if (verbose)
 211                                 fprintf(stderr, Name ": creation continuing despite oddities due to --run\n");
 212                 }
 213         }
 214
 215         /* If this is  raid5, we want to configure the last active slot
 216          * as missing, so that a reconstruct happens (faster than re-parity)
 217          */
 218         if (force == 0 && level == 5 && first_missing >= raiddisks) {
 219                 insert_point = raiddisks-1;
 220                 sparedisks++;
 221                 array.active_disks--;
 222                 missing_disks++;
 223         }
 224
 225         /* Ok, lets try some ioctls */
 226
 227         array.level = level;
 228         array.size = size;
 229         array.raid_disks = raiddisks;
 230         /* The kernel should *know* what md_minor we are dealing
 231          * with, but it chooses to trust me instead. Sigh
 232          */
 233         array.md_minor = 0;
 234         if (fstat(mdfd, &stb)==0)
 235                 array.md_minor = MINOR(stb.st_rdev);
 236         array.not_persistent = 0;
 237         if (level == 5 && (insert_point < raiddisks || first_missing < raiddisks))
 238                 array.state = 1; /* clean, but one drive will be missing */
 239         else
 240                 array.state = 0; /* not clean, but no errors */
 241
 242         /* There is lots of redundancy in these disk counts,
 243          * raid_disks is the most meaningful value
 244          *          it describes the geometry of the array
 245          *          it is constant
 246          * nr_disks is total number of used slots.
 247          *          it should be raid_disks+spare_disks
 248          * spare_disks is the number of extra disks present
 249          *          see above
 250          * active_disks is the number of working disks in
 251          *          active slots. (With raid_disks)
 252          * working_disks is the total number of working disks,
 253          *          including spares
 254          * failed_disks is the number of disks marked failed
 255          *
 256          * Ideally, the kernel would keep these (except raid_disks)
 257          * up-to-date as we ADD_NEW_DISK, but it doesn't (yet).
 258          * So for now, we assume that all raid and spare
 259          * devices will be given.
 260          */
 261         array.spare_disks=sparedisks;
 262         array.failed_disks=missing_disks;
 263         array.nr_disks = array.working_disks + array.failed_disks;
 264         array.layout = layout;
 265         array.chunk_size = chunk*1024;
 266
 267         if (ioctl(mdfd, SET_ARRAY_INFO, &array)) {
 268                 fprintf(stderr, Name ": SET_ARRAY_INFO failed for %s: %s\n",
 269                         mddev, strerror(errno));
 270                 return 1;
 271         }
 272
 273         for (dnum=0, dv = devlist ; dv ; dv=dv->next, dnum++) {
 274                 int fd;
 275                 struct stat stb;
 276                 mdu_disk_info_t disk;
 277
 278                 disk.number = dnum;
 279                 if (dnum >= insert_point)
 280                         disk.number++;
 281                 disk.raid_disk = disk.number;
 282                 if (disk.raid_disk < raiddisks)
 283                         disk.state = 6; /* active and in sync */
 284                 else
 285                         disk.state = 0;
 286                 if (strcasecmp(dv->devname, "missing")==0) {
 287                         disk.major = 0;
 288                         disk.minor = 0;
 289                         disk.state = 1; /* faulty */
 290                 } else {
 291                         fd = open(dv->devname, O_RDONLY, 0);
 292                         if (fd < 0) {
 293                                 fprintf(stderr, Name ": failed to open %s after earlier success - aborting\n",
 294                                         dv->devname);
 295                                 return 1;
 296                         }
 297                         fstat(fd, &stb);
 298                         disk.major = MAJOR(stb.st_rdev);
 299                         disk.minor = MINOR(stb.st_rdev);
 300                         close(fd);
 301                 }
 302                 if (ioctl(mdfd, ADD_NEW_DISK, &disk)) {
 303                         fprintf(stderr, Name ": ADD_NEW_DISK for %s failed: %s\n",
 304                                 dv->devname, strerror(errno));
 305                         return 1;
 306                 }
 307         }
 308
 309         if (insert_point < MD_SB_DISKS) {
 310                 mdu_disk_info_t disk;
 311                 disk.number = insert_point;
 312                 disk.raid_disk = disk.number;
 313                 disk.state = 1; /* faulty */
 314                 disk.major = disk.minor = 0;
 315                 ioctl(mdfd,ADD_NEW_DISK, &disk);
 316         }
 317
 318         /* param is not actually used */
 319         if (runstop == 1 || subdevs >= raiddisks) {
 320                 mdu_param_t param;
 321                 if (ioctl(mdfd, RUN_ARRAY, &param)) {
 322                         fprintf(stderr, Name ": RUN_ARRAY failed: %s\n",
 323                                 strerror(errno));
 324                         return 1;
 325                 }
 326                 fprintf(stderr, Name ": array %s started.\n", mddev);
 327         } else {
 328                 fprintf(stderr, Name ": not starting array - not enough devices.\n");
 329         }
 330         return 0;
 331 }